1. Field of the Invention
The present invention relates to a technology for processing image data obtained by reading an image by an image reading unit.
2. Description of the Related Art
In recent years, with the development of an image reading device that includes a line sensor that is formed with a photoelectric conversion element such as a charge-coupled device (CCD) and the development of a writing device that uses laser irradiation, a copier system has made an advancement from an analog copier to a digital copier that creates a copy of an image using digitalized image data of an image. The digital copier has improved the compatibility with other digital devices that process digitalized image data. That has resulted in incorporating various functions, such as a copier function, a facsimile (FAX) function, a printer function, and scanner function, in one device, which is known as a multifunction peripheral (MFP).
Moreover, with the advancement in the MFP-related technology (e.g., increase in storage capacity and decrease in manufacturing cost of a memory device such as a hard disk drive (HDD), increase in communication speed in a communication technique such as a network communication, enhancement in throughput of a central processing unit (CPU), enhancement in an image processing technique such as a data compression technique for digital image data, etc., a wide variety of functions is being installed in the MFP. Consequently, the usage of the MFP is also getting more diversified. For example, a compact-sized MFP can be placed near a personal computer (PC) such that a user can use various functions of the MFP. A medium-sized MFP can be shared by a plurality of PCs, such as in units of department or section in a company, to make use of its relatively sufficient productivity along with functions such as sorting, punching, and stapling. A large-sized MFP having high productivity, high quality, and a variety of functions can be used in a department that mainly provides a copy-related service in a company or in a company that are regularly engaged in the copy-related service.
In this way, the MFP has been diversified. Some functions are sharable among the MFPs of different classes, while other functions are uniquely required in the MFP of a particular class. For example, the large-sized MFP is desired to perform finishing processes such as punching, stapling, and folding upon completion of printing or perform processes of copying and electronic filing in a simultaneous manner. On the other hand, the compact-sized MFP is desired to have enhanced Internet FAX function and PC-FAX function or perform high-quality image printing on a specific paper for personal use.
For such a diversified MFP market, the MFP has been developed and provided with a system that includes a set of functions unique to each class. Meanwhile, it is desired to convey information in a faster, accurate, reliable, easy-to-understand, and effective manner considering the importance of the information in business. With the advent of a technology such as increase in speed of a communication technique, increase in storage capacity and reduction in cost and size of a memory device, and enhancement in PC performance, more and more new functions are being provided for effectively processing digital data. Particularly in the MFP that processes digital image data, more and more new functions are being provided and integrated.
For example, Japanese Patent Application Laid-open No. 2000-165655 discloses an image processing apparatus that enables a wide variety of image synthesis due to its ability to handle a wider zoom ratio and eases restrictions on the use of readable image area due to the storage capacity of a memory.
Japanese Patent Application Laid-open No. H07-78245 discloses an image processing apparatus that can perform high-speed image processing without causing a degradation of image quality even without a page memory for a full-sized image.
Meanwhile, as described above, the compact-sized MFP can be placed near a PC such that a user can use the MFP for various functions. Thus, such compact-sized MFP has become popular among different types of users such as users in small offices/home offices (SOHO), home users, users at mid-size offices, and users at large offices. That has resulted in diversification of user demands regarding functions of the compact-sized MFP. Because of the continuous development of new MFP functions, the configuration of the compact-sized MFP has become more complex. As a result, it is becoming increasingly difficult to maintain low manufacturing cost, which is a feature advantage of the compact-sized MFP, while keeping up with the new MFP functions.
As described above, the image forming apparatus disclosed in Japanese Patent Application Laid-open No. 2000-165655 eases restrictions on the use of readable image area that is restricted due to the storage capacity of a memory. For that, the image forming apparatus switches a mode of zoom processing according to the amount of usable memory or according to whether an image rotation is performed with the use of the memory. However, because such easing of restrictions does not correspond to the nature of the image processing, it is difficult to constantly perform the image processing appropriate for a given condition.
As described above, the image processing apparatus disclosed in Japanese Patent Application Laid-open No. H07-78245 performs image processing even when the page memory for a full-sized image is not installed therein. For that, the image forming apparatus determines, depending on the size of image data to be processed, whether to use a frame memory installed therein as the page memory or as an image registration memory. However, because the abovementioned method does not correspond to the nature of image processing, it is difficult to constantly perform the image processing appropriate for a given condition.